In recent years, it has been known to combine a drive control inverter provided in an electric rolling stock or a power supply facility provided in a substation on the ground or the like with a power storage system to which a power storage device such as a secondary battery and an electric double-layer capacitor is applied, so that excess regenerative power generated by braking a vehicle is stored in the power storage device and the stored power may efficiently be used for accelerating the vehicle or addressing drops in the line voltage, which enables efficient use of the kinetic energy of the vehicle (see for example Patent Documents 1 and 2).    Patent Document 1: JP-A-2003-199354    Patent Document 2: JP-A-2005-206111